Resistance heating coil
Using the Joule effect of electric current to convert electrical energy into thermal energy to heat objects. It is usually divided into direct resistance heating and indirect resistance heating. In the former, the power supply voltage is directly applied to the object to be heated. When current flows, the object itself
generates heat. Objects that can be directly resistance heated must be conductors with high resistivity. Since the heat is generated inside the object itself, it is internal heating with high thermal efficiency. Indirect resistance heating requires special alloy materials or non-metallic materials to make heating elements, which generate thermal energy and transfer it to the object to be heated through radiation, convection, and conduction. Since the object to be heated and the heating element are separated, the type of object to be heated is generally not limited, and operation is simple.
The materials used for heating elements in indirect resistance heating generally require high resistivity.
